The present work was aimed at estimating the mode I strain energy release rate at crack initiation in woven-ply thermoplastic (TP) based laminates at high temperature T>T g . A linear spectral viscoelastic model and a generalized Norton viscoplastic model were used to account for the time-dependent behavior of TP-based composite laminates, which are exacerbated at high temperature. To precisely evaluate the fracture parameters (e.g. R-curves) in TP composites, a study on the mesh type and its refinement was carried out. Using the finite element code Cast3m, the G θ method was applied in order to test its capability to determine the mode I strain energy release rate for different testing conditions. (5)-Harness satin weave carbon fabric reinforced PolyPhenylene Sulfide (5HS C/PPS) laminates have been studied with two different stacking sequences: a Quasi-Isotropic (QI) sequence characterized by a fibre-dominated behaviour and an Angle-Ply (AP) sequence whose behaviour is matrix-dominated. Tensile tests have been simulated on Single-Edge-Notch (SEN) specimens (with different notch lengths) subjected to quasi-static loadings in order to investigate the effect of time-dependent behaviors on translaminar failure and strain energy release rate. The R-curves have been derived from the computation of the strain energy release rate and the corresponding crack length. Ultimately, it is possible to build R-curves based on the evaluation of fracture toughness for different ratios a/w and to compare these curves to the ones obtained from experiments.